1. Field of the Invention
The present invention relates to a frequency multiplier and mixer circuit forming one circuit capable of executing both a frequency multiplying operation and a mixing operation.
2. Description of Related Art
As is well known, in the case of requiring both of the frequency multiplying operation and the mixing operation, for example, a frequency multiplying circuit and a mixing circuit, which are independent of each other, have been coupled with a bandpass filter.
However, with this prior art frequency multiplying and mixing circuit it has been difficult to achieve a wide operating band. In addition, if the frequency multiplying circuit and the mixing circuit are implemented in a bipolar and MOS semiconductor integrated circuit process, since terminals are required to externally connect the filter, the number of external terminals in the semiconductor integrated circuit has to be increased.